Where Do Bats Prefer For Their Hibernation Sites?
When bats hibernate, they often hang off the roofs of mines and caves in very large groups. There is still no proper explanation for this behaviour; it is often put down to a need to conserve heat, but isolated bats of the same species are, in fact, able to maintain similar body temperatures. Many bats actually prefer to hibernate at very low temperatures and often select cave mouths rather than the warmer areas inside. It may be that the dense crowding keeps the temperature of the bats as constant as possible and minimises the effects of draughts. Several factors determine which hibernating site the bats choose. Seclusion is important, as well as protection from rain, snow and high winds. It is also important for the humidity to be high. If it is not, the evaporation of the bats’ body moisture means that they have to wake up – an energy-consuming process, since all the body systems have to be started from cold – so that the lost moisture can be replaced by a quick drink.
